@DH, after sending a transaction using old coins existed and generated prior to the block 460,000 couldn't either parties(nodes) be programmed some how to cross reference the both chains to see if a transaction is being double-spent?
Yep, so you'll know, but you can't do anything about it.
and how can someone send your coins from other chain without your permission if they don't have the private key?
They don't need it. The only thing you need the private key for is to sign the transaction. You've already signed that transaction, so it's just as valid on the other chain.
Also miners could as well ignore all transactions and mine empty blocks for as long as it takes to sort things out correct?
Sure, but why would they?
You are saying that if bitcoin splits in two chains then we could literally double spend more than 16.3M
BTC successfully and get away with it?
Wouldn't that destroy everything that bitcoin claimed to do and be?
Which one is better in your opinion, supporting SW and activating it and if we do then could we hard fork if it back fired and wouldn't that be the reasonable solution?